This research is aimed at extending our investigations into the occurrence of human carcinoembryonic isoferritins and their possible value in serodiagnosis of cancer. Attempts will be made to determine whether an "abnormal" isoferritin we have found in human hepatoma and in early fetal livers is a true carcinoembryonic protein or occurs in non-malignant disease or normal adult tissues. Particular attention will be paid to isoferritins in placenta, ovarian carcinoma, and Hela cells, tissues presently receiving intensive study in the Cancer Center in this University as models for phenotypic expression of carcinoembryonic proteins. Preliminary evidence indicates that all three tissues contain isoferritins corresponding to carcinofetal forms found in hepatoma. These isoferritins will be isolated from placenta and Hela cells for detailed comparative structural analysis with normal tissue isoferritins. Attempts will be made to develop monospecific antibodies against the carcinoembryonic isoferritins in placenta for serodiagnostic purposes. In related studies, investigations will be made into the occurrence of carcinoembryonic isoferritins in lines of Hela cells characterized by their content of the Regan isozyme, a carcino-placental form of alkaline phosphatase. Factors regulating the genetic expression and biosynthesis of the Hela ferritins will be compared to those operating in normal cells. Attempts will be made to correlate the phenotypic expression of the carcinofetal ferritins with the cell genotype.